Hydrodynamic machine



March 2, 1954 w FERRls 2,670,689

HYDRODYNAMIC MACHINE Original Filed May 25, 1944 6 Sheets-Sheet l I le INVENTOR WALTER FER RIS A TORNEY March 2, 1954 W. FERRIS HYDRODYNAMIC MACHINE original Filed May 25, 1944 6 Sheets-Sheet 2 if l l N INVENTOR WALTER FERRls f N BY ATTO NEY March 2, 1954 HYDRODYNAMIC MACHINE Original Filed May 25., 1944 6 Sheets-Sheet 3 Q ,29. 426 Uy/'yin NVENT 75 WA R FER ATTORNEY w. FERRls 2,670,689

March 2, 1954 w. FERRls HYDRODYNAMIC MACHINE 6 Sheets-Sheet 4 Original Filed May 25, 1944 FIG. 7

INVENTOR WALTER FERRIS ATTORNEY March 2, 1954 w. FERRIS 2,670,689

HYDRODYNAMIC MACHINE 6 Sheets-Sheet 5 Original Filed May 25, 1944 l VENTOR 'WAL FERRIS ATT RNEY March 2, 1954 w. FERRIS HYDRODYNAMIC MACHINE 6 sheets-sheet 6 original Filed May 25, 1944 INVENToR WALTER FERRIS WBYWP/ TTORNEY Patented Mar. 2, 1954 HYDRODYNAMIC MACHINE Walter Ferris, Milwaukee, Wis., assignor to The Oilgear Company, Milwaukee, Wis., a corporation of Wisconsin Original application May 537,346, now Patent No. uary 16, 1951. Divided 25, 1944, Serial No. 2,538,194, dated .lanand this application July 21, 1948, Serial N0. 39,866

7 Claims. l

This application is a division of application Serial No. 537,346 led May 25, 1944, now Patent No. 2,538,194.

rI'he invention relates to hydrodynamic inachines of the type having a plurality of vanes slidably fitted in slots formed substantially radially in a rotor, a spacer ring arranged around. the rotor and spaced therefrom, cheek plates arranged upon opposite ends of the rotor and held in spaced relation by the spacer ring, and a vane track arranged around the rotor inside of the spacer ring and including a plurality of bridges which cooperate with the vanes to divide the space between the rotor and the spacer ring into high pressure and low pressure chambers.

Such a machine ordinarily has two diametrically opposed sealing bridges which are arranged close to the rotor and two working bridges which are spaced 90 from the sealing bridges and are spaced from the rotor when the machine is performing useful work at which time the outer ends or the vanes ride along the vane track and pass through the low pressure and high pressure chambers successively. If the rotor is rotated, the vanes passing across the working bridges will transfer liquid from the low pressure chambers to the high pressure chambers and the machine will function as a pump. If motive liquid is supplied to the high pressure chambers, it will act upon the outer end portions or" the Vanes in contact with the working bridges and rotate the rotor, thereby causing the machine to function as a motor.

The Vouter ends of vanes passing through the high pressure chambers are subjected to the pressure therein. In order to prevent this pressure' rcmmoving those vanes inward out of engagement with the vane track, one of the cheek plates is provided in its inner face with vane lslot ports which are spaced radially inward from the high pressure and low pressure chambers and with which the inner ends of the vane slots register successively as the rotor rotates, and the vane slots that are radially inward from the high pressure chambers are supplied with liquid at a pressure at least as high as the pressure in the high pressure chambers.

In prior machines, the vane slot ports that are radially inward from the high pressure chambers communicate through holes in the cheek plate with grooves which are formed in the outer face of the cheek plate and are connected to a source of high pressure liquid. The outer face of the cheek plate is inV contact with a flat surface which closes the open sides of the `grooves but (Cl. 10S- 136) .teristic mentioned above.

Another object is to provide a cheek plate that will not be deected by the liquid supplied to the vane slot ports therein.

Another object is to provide a hydrodynamic machine with means for supplying liquid at a low pressure to the vane slot ports to initially urge the vanes against the vane track and means to automatically increase the pressure of the liquid in response to the pressure at the outer ends of the vanes exceeding a given value.

These and other objects and advantages are obtained in the embodiment of the invention shown in part in detail and in part schematically in the accompanying drawings in which the views are as follows:

Fig. l is a central longitudinal section through a machine in which the invention is embodied, the view being taken on the line IME of Fig. 2 and the lower part of the `casing being broken away in order to show the working parts on a ,larger scale.

Fig. 2 is a transverse section taken across the end of the rotor as indicated by the line 2 2 of Fig. 1.

Fig. 3 is an enlarged perspective view of one of the vane track sections shown in Fig. 2.

Fig. d is a view taken in the plane oi the line flof Fig. 2 but drawn to a larger scale and showing the means for connecting the vane track sections to the bridges and the means for movling the bridges radially outward.

Fig. 5 is a view drawn to the same scale as Fig. 4 and illustrating the mechanism for Inov- Aine a bridge toward the rotor and for controlling the movement of the bridge away from the rotor, the view being taken on the longitudinal centerline of the machine in the same plane as Fig. 1 and as indicated by the line 5 5 of Fig. 6 but it shows the bridge in a position different from that shown in Figs. l and 4.

Fig. 6 is a fragmentary section taken on the line 6-6 of Fig. 2 and showing the arrangement of the springs for urging a bridge radially outward, the view being drawn to the same scale as Fig. 5.

Fig. 7 is a view taken approximately on the irregular line 'l-l of Fig. 8 and showing the radial portsthrough which liquid iilows to and from therotor.

Fig. 8 is a transverse section taken on the line 8-8 of Fig. 1 and illustrating the passages through which liquid flows to and from. the portsshown in Fig. 7.

Fig. 9 is a diagrammaticl View' illustrating the hydraulic circuits of the machine.

The machine shown in the drawings is intended to function as a pump and it will berdescribed as such but the machine will function asza motor if it is supplied with motive liquid, and it isz to be understood that the present invention is in no way limited to a pump.

As shown, the pump has its mechanism arranged within a casing l having formed therein a cylindrical recess 2 which vis larger in diameter at' its front than at its rear to receive an end head Swhich closes recess 2 and has a peripheral vflange 4 `formed thereon and extending around the inner periphery of the enlarged part of recess o 2. Flange 4 has the` same inner diameter as the rear part oi `recess 2, an upper portion of flange 4 being cut away to accommodate a control mech-- anism' aswill presentlybe explained.

Recess 2 containsa spacerl ring 5 which is lltted in the' rear' part' thereof and within the rear part of flange 4. A rotorii'- is arrangedinside of spacer ring 5 and provided with a plurality of substantially radial vane slots l' each oi which has a vane 8 slidably litted therein.

When the machine is performing useful work, each vane moves outward andY draws liquid into its yslot duringl one` part of a revolution oi the rotor and it moves inward and expel's liquid from its slot during the succeeding part of a revolution of the rotor. The vane slots cannot be eX- tended radiallyV inward but veryv little beyond the innermost positions of the vanes without dangerousl'y weakening therotor. Consequently, il each vaneV slot `had the same width throughout' its length, the flow of liquid' to the inner end of a vane would be greatly restricted when the van-e `was in its innermost position. In the present instance, the rotor is considerably longer than the rotors of the pri-or machines and, inV order to' provide unrestricted flow of liquid tothe inner end of' each vane throughout the entire length thereof, the inner end of each vane'slot 'l is enlarged in the form of a circular bore-as shown in Figs. Zand 7.

Spacer ring 5 and rotor are arranged between a cheek plate 9", which is fitted in the rear part of recess 2- and engages the rear wall thereof as' shownin Fig. l, and a cheek plate |36 which is fitted' withinY flange 45 and engages a gear pump cover plate H1 which is also: arranged vnuthin flange 41 and engages the inner face of endhead 3. The cheek plates', spacer'rin'g, gear pump cover pla-te and end head are rigidly clamped together by' a plurality oi? bolts. l2 whiclfi extend therethrough` and are threaded intoV the rear part of casing` t, spacer ring 5 being tust enough longer than rotor 6'? to provide running clearances between the ends. of the rotor and the adjacent faces oli thex cheek plates;

Rotor' El is splined upon and driven by aA drive shaft I6 which extends through cheek plates 9 and t0 and through cover plateY H and is journaled in suitable bearings carried by casing l and endf 'head1 3 respectively. Driveshaft ti also drives a gear pump having one gear l1 splined upon shaft IG and its other gear i8 meshing with gear I1 and `iournaled upon a stub shaft I9 which is xed in end head 3. Gears I1 and I3 are arranged in a suitable pumping chamber 2l) which is formed in end head 3 and has its' open side closed by cover plate H. Pumping chamber 2U communicates with an extenal circuit through passages which do not appear in Fig. 1 but are shown schematically in Fig. 9.

outer ends: of. vanes 8 engage a smooth track surface formed upon the inner periphery of an endless vane track of the type described and; claimed in Patent No. 2,538,193, The vane track consists primarily of four identical bridges 2li?,v 24", 241' and; 24, which are equally spaced around rotorr E- as-shown in Fig. 2, and four identical track sections 25, 25e, 25h and 25C which are arranged between adjacent bridges and pivotally connected thereto. The track sections are extensible and' the`v bridges are adjustable toward and from the rotor to vary theV displacement of the pump, the track surface on each' track' secti'on is concave, the track surface on each bridge is concave intermediate its ends for a distance at least as great as the angular distance between the outer ends 'of two adjacent varies and it is convex adjacentV each of its ends so that' i't is tangent tol the concave surfaces on the adjacent track sections in all positions of the bridges, and the ends of the track sections and bridges are,` so shaped as to provide an; unbroken path for the varies as explained in said application.

As shownin Fig. 3, each tracll: section includes two parts 2b and 2l which are telescopicall-y connected to each other by two guide segments 2li and 2% arranged upon opposite sides thereof' and eachA segment i's-pref'erably Xed to one of the parts as by means of -a pin' 30?. Each track section has a concave track surface formed upon its inner face and, as explained in Patent No: 2,538,193', segments Z8 and 29 are telescopically connected to parts E and 21 in sucha manner that they hold the track surfaces thereon in circumferential alinement with each other whilepermitting parts Z and 21' to move toward andfrom each other to vary the length of the vane track, the adjacent ends-of parts 2B and 21 being complementary to each other and extending diagonally inwardfrom opposite' sides to provide an unbroken path for the varies in all positionsy o'parrts B16-and 2l.

In order to provide the smoothest possible radial movements of the vanes', the tracky sections should' be-pi'votally connected to adjacent bridges at points spaced as far radially outward as may be conveniently possible within the available space. To this' end, each track section part 2B has twoposts 3i' and 3i? rigidly secured thereto, each track section part 275 has two posts 33 and 3ft' rigidly secured thereto, and the outer endsof the posts are provided with suitable holes so that the postsl may be pivotally connected to the bridgesl as will presently be explained.

Bridges 213-, 24a, 2th and 215 are arranged, respectively, inrecesses 35; 35', 35h and 35 which are formed in spacer ring 5 as shown in Fig. 2. Each bridge is closely fitted between the sides of its recess and between cheek plates 9" and i0, so that the bridges the' van'es in contact therewith divi-:ie the space between the periphery of rotor E and the inner periphery of spacer ring 5 into-'alternate intake and discharge chambers'. in prior pumps of' this character, the intake and discharge chambers are connected to* opposite sides of an external circuit through ports which 'extend axially therefrom through one of the cheek plates. This arrangement is entirely satisfactory in pumps of the sizes ordinarily used but it is not at all satisfactory in large pumps for the reason that Ian increase in capacity does not result in a proportional increase in the area of axial ports.

The pump illustrated in the drawings is adapted to be made in large sizes, that is, it is capable of having a large volumetric capacity. In order to avoid the head losses which would occur if it were provided with axial ports, each of track sections 25, e, 25h and 25 is provided with a radial opening or port 4i) as shown in Fig. 3. The ports 4i! in track sections 25, 25e, 25b and 25 communicate, respectively, with four ports 4I, Ale, Mb and 4in which, as shown in Figs. 2 and 7, are formed in spacer ring; 5 and in cheek plate B.

As shown iu Figs. 7 and 8, ports 4I and 41h f communicate, respectively, through two passages 42 and 42D with an approximately semi-circular passage 43 which is formed in the head end of casing l and has two branches 54 and 45. Ports Ma and 4I@ communicate, respectively, through two passages 42a and 42 with a substantially annular passage 6 which is formed in the head end of casing l radially inward from passage 43 and has two branches t1 and t8. Branch passages llt and 41 connect the pump to an external circuit and branch passages and 48 connect the pump to an automatic suction valve as will presently be explained.

As previously explained, each vane track section is pivotally connected to adjacent bridges by means of the posts 3l, 32, 33 and 34 shown in Fig. 3. The two posts fixed to each track section part 2e or 2l' extend intotwo recesses four Iof which are formed in each bridge, and both of these posts are journaled upon a pivot pin or shaft which extends through the bridge and the cheek plates. For example and as shown in Fig. 4, the posts Si and 32 which are iixed to part 26 of track section 25 extend, respectively, into two recesses 5i and 52 which are formed in bridge 24, and both of posts 3i and 32 are journaled upon a long pivot pin 53 which extends through the bridge and has its opposite ends arranged in two recesses 5s and 55 which are formed in cheek plates 9 and i9 respectively. One end of track section 25 is similarly connected to the other side of bridge 2s and the other ends of track sections 25 and 25C and both ends of track section 25a and 25h-are similarly connected to the other bridges. Y

Pivot pin 53 exten-ds through two bushings 56 and 51 which are fixed in bridge 24 and extend from opposite sides thereof into recesses 56 and 55 to provide stops tc engage the inner walls of recesses 513 and 55 and positively limit the inward movement of the bridge and thereby prevent the vane track from being urged against the periphery of the rotor by the displacement vvarying mechanism to be presently described.

Pin 53 provides an anchor for two springs 5S and 5S arranged, respectively, in two recesses 69 and 6l which are formed in cheek plates 9 and It?, respectively, and extend radially inward from the peripheries thereof into communication with recesses 54 and 55 respectively. Springs 5B and 5:y have their inner ends attached to pin 53 and their outer ends attached, respectively, to two pins 52 and G3 which are arranged within suitable slots formed in the cheek plates and extending across recesses 5B and 6| respectively.

Pins 52 and 63 bear against the inner ends'of their slots and enable springs 58 and 59 to urge bridge 24 outward. The other end of track section 25 and both ends of the other track sections are similarly connected to the adjacent bridges so that the inward movement of each bridge is limited by stops 55 and 51 and, as shown in Fig. 6, each bridge is urged outward by two springs 58 and two springs 59.

As previously explained, bridges 2li, 24a, 2lib and 2stc are closely iitted, respectively, in recesses 35, 35a, 35h and 35c and between cheek plates 9 and I. The arrangement is such that motive liquid may be directed to and from the outer ends of the recesses to enable each bridge to function as the piston and its recess to function as the cylinder of a servo-motor for moving that bridge toward the rotor. The flow of liquid to and from recesses 35, 35a, 35h and 35c is controlled, respectively, by four follow-up valves S1, 61a, 511 and 61.

Since the ow control means for all four bridges are identical, a description of one will sufce for all. For example and as shown in Fig. 5, bridge 2'4 is controlled by a valve B1 which is tted in a bore 63 formed in bridge 24 and in spacer ring 5. Valve 61 controls con1munication between a supply passage B9 and a passage 1B and between passage 1i! and a discharge passage 1l all of which are formed in bridge 2t. Passage it connects the outer end of recess 35 to bore 68 at a point intermediate the ends thereof. Passage 69 communicates with bore 66 at a point spaced radially inward from passage i8 and it is constantly supplied with motive liquid as will presently be explained. Passage 1! communicates with bore 58 at a point spaced radially outward from passage 1D and it connects bore 68 to a passage 12 extending through cheek plate 9 into communication with an annular passage 13 which is formed in the periphery ofcheek plate 9 and in the rear face of cheek plate i) adjacent to periphery thereof.

Passage 13 is connected to drain through a passage 14 having a check valve 'i5 arranged therein. Likewise and as shown in Fig. 1, gear pump cover plate H has an annular passage 1S formed in its periphery and connected to drain through a passage 11 having a check Ivalve 13 arranged therein. Check valves 'i5y and 'i3 offer a low resistance, such as 10p. s. i. to the discharge of liquid therethrough to thereby `keep casing l lled with liquid and to provide lubrication for the bearings.

Valve 61 (Fig. 5) has formed therein a cannelure which is exactly the same length as the distance between the adjacent edges of pasvsages 59 and 1I and is so located that valve 51 normally blocks communication between pas,n sages 69, 1B and 1|. 4 Y l Valve e1 is adapted to be moved inward mechanically, as will presently be explained and, when it moves inward, it opens passage tato permit liquid to flow therefrom through bore .E8 and passage vii to thejouter end of cylinder 35 and move bridge Ellinward, and bridge V2li in moving inward will tend to close passage 69 as fast as valve 61 opens it so that movement of bridge 2li ceases substantially as soon as movement of valve t? ceases.

Valve E1 is urged outward by a spring 1S arranged in the inner end of bore 68 and in a recess formed in the inner end of valve 61. When valve `61 is permitted to move outward, it opens passage 1l and then the forces exerted upon bridge 2L by theppressures inthe pump and by springs 58. and a9 will move bridge 2t outward and cause it to expel liquid from the outer end of recess 35 through passage Mt bore dit and passages; 'l-l, l2, i3 and 'ts to drain. Bridge 24 in moving outward will tend to close passage 'H as fast as valve 61. opens; it so that. movement of bridgeV 24 ceases substantially as soon as movement of valve S1 ceases.

When valve $1 is stationary, bridge 2liy is held stationary for the. reason that liquid cannot new into recess 35 to move. bridge Zbl inward and the licuiid` trapped recess. 35 prevents bridge 24 from being. moved outward by the forces exexerted. thereon. It bridge 2.4 should move in one direction or the other from an. adjusted position, it; would open passage e9: or passage 11i. just as soon as it started to move. and opening one or the other of those passages would cause bridge 2k to be returned to its adjusted position before it had moved an appreciable distance thererom.

Valves 61 618 61.1 and 6,1 are. urged outward by their springs le into engagement with a cam ring 80A which is. .arranged around spacer ring 5 and rotatably supported within the enlarged part of recess` 2 by an annular roller bearing 8l as shown in Figs. 1 and 2', axial movement of cam. ring s0 being prevented by nange 4 and the shoulder ormed by enlarging the front part of recess 2.

The inner periphery of cam ring 80. constitutes a cam track which is concentric with rotor S except at four places where it is recessed to. term four cam surfaces 82, 8221 82? and sie for effecting operation or valves- (Si, dla, s'b and tic respectively. The parts are so. proportioned that a= valve engagement with a concentric portion oi the cam track on cam. ring 8a will be held in. its innermost position and a` valve in engageu ment with one. of the cam surfaces will have been moved, outward trom its innermost position a. distance' proportional to the distance the end of the valve moved along the. cam. surface from the adjacent concentric portion of the cam track.`

Since each bridge moves. with its valve and occupies the same relative position as. its valve as previously explained, a bridge will be in its innermost position. or close to rotor E. when its valve is in. engagement with a concentric portion u oi. the. cam track and it will` move. outward. 'away trom rotor E when. one of the camsurfaces moves into alinement with its valve and. permits the valve to move outward.

The four cam surfaces are so located that only two valves can engage cam surfaces at. the same time but all iour valves can engage. concentric portions of the. cam track at the same time. Whenl cam ring' 20 is. in its. neutral position,v all four valves are in engagement with concentric portionsioi the cam track so. that all four bridges are. in their innermost positions and pump displacement. is. zero.

When cam ring 80. is rotated from its neutral position clockwise in respect. to Fig. 2, valves 61a and BHG will ride along the concentric portions of. the cam track` so that bridges 2&8 and' 24 are held. in their innermost positions but valves 61 and. 61? willride, respectively, onto cam surfaces 82 and 82b which will permit valves 6l and Gv'lb tomo-ve outwardk and.. cause bridges 24 and Mb to move outward.

- Holdingbrid'ges 24EL and 24 close tothe rotor andV moving bridges 24. and. 24haway from the rotor', causesA the pump to discharge liquid in one direction at a rate dependent upon. they distances that' bridges 24 and 2411 are. moved from their innermost or zero displacement positions. For example, if rotor 6- rotated the direction of; the arrow, the vanes passing across bridge 24 wil-l transfer liquid from port M to.. port All and the vanes,` passing acrossbridge 241 will transfer liquid from port 4 Ib to port 4 I*EL so that the pumpy draws liquid through ports 4|. and 4th and discharges it. through portsY 4t and 41., If camI ring lilly is rotated far enough toy permit valves 6.1 and 61h to move outward until they have caused bridges 24 and 2lib to stall. against. the outer ends of recesses: and 35has shown in Fig. 2,. pump displacement will be. maximum and the pump will deliver liquid at its maximum rate through ports 4ta and MC.

When cam ring 8D. is. rotated counterclockwise from theA position shown in Fig. 2, cam surfaces 82 and. 82h will forcev valves. 61 and. 611 inward which will causeV bridges 2.4 and Zlib to. move inward, and reduce pump. displacement until cam ring 8l) reaches its. neutral position at which time bridges 24 and 2lib will have been moved to their innermost positions and pump displacement will be zero.

Continuedrotation of cam ring 8b will bring cam surfaces. 82ab and 82C- into alinement with valves. 61a and 61 which Will then move outward and cause bridges 24a and 24c to move outward but valves B1 and STP will remain in4 contact with concentric portions. of the cam track so that bridges 2li and 2li@ are held in their innermost positions, With bridges 24 ancll2ll,b in their innermost. positions and bridges 24a and' 28C moved outward, thev pump will function as previously explained but it will deliver liquid` in the opposite direction at a rate dependent upon the distances bridges 24e and. 2G are moved from their innermost positions. Bridges which are arranged close to the periphery of' the rotor. are commonly designated as sealing bridges because. they merely provide a seal between the adiacent inlet and discharge ports. Bridges which are spaced from the. periphery or" the rotor are, commonly known as "working bridges because vanes passing thereacross transfer liquid from. the inlet port on one side. thereof to the discharge port on they other side thereof. Since bridges 24, 24a, 24', and 2lb are movable toward.' and from. the rotor as explained abovcthey function alternatively as sealing and working bridgesl Cam ring is rotated through a pin 83 (Figs.

l and 2) which connects it to a link 84 and to the connecting rod 85 of a piston. 8S ntted in a cylinder 8T which is formed in or connected to casing. i' and to which motive liquid is constantly supplied through a channel 88 from a suitable source. For example, channel 88 maybe connected to gear pump H-l as shown in Fig. 9. i Link 8.1i connects pin 83 to one end of a lever Sil the other end of which is pivotally connected to casing I by a shaft 9i. Lever 9'!) isv provided intermediate its ends with a roller 92 to engage the inner end of a. sleeve 93 having a piston 94 arranged thereon. and closely fitted in a cylinder L Piston 9,4 and cylinder 95' constitute a servomotor which is controlledv by a rotary valve 95 journaledin sleeve 93 and in the head of cylinder 95 and providedy on its outer end with means, such as` a lever S1 for rotating it, Liquid for operating servo-motor 94-95 flow-s to andfrom cylinder 9.5 through a port.- 98., extending. through the wall of sleeve 93 and normally arranged between two spiral grooves 99 and itt which are formed in the periphery of valve 96. Groove 99 is drained into casing I through at least one hole IGI formed in the inner end of sleeve 93. Groove Illt` communicates with a passage It? formed within valve 96 and communicating with a port |93 which is formed in the head of cylinder 95 around valve 96 and connected by a channel |64 to a supply of liquid so that groove itt is constantly supplied with motive liquid. For example, channel Its may be connected to gear pump IT-IB' as shown in Fig. 9.

When valve 96 is rotated counterclockwise as viewed from the right end of Fig. 2,. groove It@ will move into registry with port 93 and then liquid will now from channel |34 through port ID3, passage m2, groove its and port 98 into cylinder 95 and cause piston :'34 to move vtoward the left and swing lever countercloclrwise upon shaft 9|. Lever 9c will move link 9d and pin 83 toward the left to thereby rotate cam ring 80 ccunterclockwise in respect to Fig. 2 and to also move connecting rod 85 and piston 8S toward the left, the eiiective area of piston 94 being enough greater than that of piston B to enable piston 9c to move toward the left when cylinders B'I and 95 are both supplied with liquid at the same pressure.

Piston 94 in moving toward the left will move port 98 with it and tend to close communication between groove Izlt and port 93 as fast as rotation of valve 9a opens communication therebetween. Consequently, cam ring 3c will be rotated through an angular distance exactly proportional to the angular distance through which valve 9e is rotated.

When valve 95 is rotated clockwise as viewed from the right end of Fig. 2, groove 99 will move into registry with port 98 and then the liquid constantly supplied to cylinder 81 will cause piston 86 to move connecting' rod 85, pin 83 and link B4 toward the right, pin 83 will rotate cam ring 89 clockwise in respect to Fig. 2, link 84 will swing lever 9i) upon shaft 9|, and roller 92 will move piston d4 toward the right and cause it to eject liquid from cylinder 95 through port 99, groove 99 and hole IBI into casing I. Piston 94 in moving toward the right will move port 98 with it and tend to close communication between groove 99 and port 98 as fast as rotation of valve 9S opens communication therebetween. Consequently, carn ring 89 will be rotated through an angular distance exactly proportional to the angular distance through which valve 96 is rotated.

Channels 98 and |94 may be connected to one branch of a supply channel |98 (Fig. 9) into which gear pump I'l-l discharges liquid drawn from a reservoir |99. The liquid discharged. by

gear pump Ii-IS in excess of requirements is exhausted through a relief valve |59 which enables gear pump Il-l to maintain a constant pressure, such as 85 p. s. i., in channel It. The outlet of relief valve II is connected by a channel l|| to the inlet of a relief valve H2 through which liquid in excess of requirements is exhausted into reservoir |99. Relief valve H2 is adapted to open at a pressure lower than the pressure required to open relief valve H9 so that it does not effect the pressure in channel Relief valve H2 also resists the discharge of liquid from a valve bore IIS having an automatic suction valve II4 fitted therein. Bore II3 has two annular grooves or ports H5 and Il formed in its wall and spaced from its opposite ends, and it communicates at a point intermediate ports H5 and llt with channel IIi and with a check valve l ii which permits liquid to be drawn into bore HS from reservoir H19 but prevents discharge of liquid from bore iIS into reservoir |99 except through relief valve II2.

As previously explained and as shown in Fig. 8, main ports .4i and 4Ib communicate with a passage 43 having two branches 44 and 45 for connection to an external circuit and to a suction valve respectively, and main ports 4Ia and 4i@ communicate with a passage 49 having two branches 4l' and 49 for connection to an external circuit and to a suction valve respectively. These passages are represented schematically in Fig. 9 by channels which bear the same reference numerals as the passages in Fig. 8.

As shown in Fig. 9, main ports 4I and 4Ib communicate with a channel 43 having a branch 44, which is adapted to be connected to an external circuit, and a branch 45 which is connected to the port H9 of the automatic suction v valve and provided with an auxiliary branch 45' which communicates with the right end of bore H3. Main ports 4I@ and 4|c communicate with a channel #la having a branch 4l, which is adapted to be connected to an external circuit, and a branch as which is connected to the port ||5 oi' the automatic suction valve and provided with an auxiliary branch 48a which communicates with the left end of bore H3.

The arrangement is such that, when the pump discharges liquid into ports da and 4Ic as previously explained, the liquid discharged by the pump will now through channels 49 and 4l to the external circuit since it cannot iiow into reservoir |69 for the reason that at this time valve II4 is blocking port I I5. The liquid returned from the external circuit flows through channels 44 and 43 and ports 4I and 4I to the interior of the pump. If the liquid returned from the circuit is in excess of pump requirements, the excess liquid is exhausted through channel 45, bore II3 and relief valve I I2 into reservoir 9. If the liquid returned from the circuit is insuiicient, a part or all of the liquid discharged by gear pump II-I8 into channel III will ow therefrom through bore H3, channels 45 and 43 and ports 4| and 4lb to the interior of the pump. If the liquid returned from the circuit and the liquid discharged by gear pump II-IS into channel III do not together provide sufficient liquid for pump requirements, the pump will draw liquid from reservoir |99 through check valve l il, valve bore II3, channels 45 and 43 and ports 4| and 4Ib into the pump.

When the pump is reversed so that it discharges into ports 4| and 4th, the liquid discharged by the pump will tend to flow through channels 43 and 45 and valve bore H3 into reservoir |09 but check valve I Il prevents ow into reservoir |99 except through relief valve II2 which resists the discharge of liquid therethrough and thereby causes pump pressure to rise and liquid to flow through branch 45a to the right end o bore II3 and cause valve II4 to shift toward the left and block port |I6 so that the liquid discharged by the pump cannot enter bore I I3 but must flow into the external circuit.

Liquid returned from the circuit flows to the pump through channels 41 and 46 and ports 4|a and 4I, any excess is discharged through relief valve IIZ and any deficiency is made up by gear aevde's pump il-It and also if necessary by liquid drawn through check valve l il. W hen the pump is again reversed so that it discharges into channel 46, relief valve H2 will cause pressure to rise and liquid to flow through branch '48a to the left end of bore H3 and cause valve H4 to shift toward the right to the position shown and block port H5 so that the pump cannot discharge through relief valve H2.

When the pump is running idle and when the pressure created by it is less than gear pump pressure, bridges 24 and 24h or bridges 2da and 24 may be moved inward by liquid supplied to recesses 35 and 35h or recesses 35@ and 35 from gear pump ll-i at the pressure determined by relief valve i ID which pressure is high enough to enable the gear pump liquid to exert sufficient force upon the outer ends of the bridges to move the bridges mward against the outward forces exerted thereon by springs 58 and 59 and by the low pressure acting upon the inner ends of the bridges.

If relief valve lili should be adjusted to enable gear pump l-lil to deliver liquid to the recesses at a pressure high enough to effect operation of the bridges when main pump pressure was maximum, excessive power loss and heating of the liquid would result. Therefore, the bridges are operated by liquid at gear pump pressure or main pump pressure whichever is the higher.

As shown schematically in Fig. 9, gear pump supply channel S is connected to a distributing channel l2i through a check valve i221 which permits liquid to flow from channel it into channel |21 but prevents flow in the opposite direction. Channel i2l is connected to channel 113 through a check valve 23 and to channel is through a check valve [2li so that pressure can extend from channel i3 or channel 4S into channel iii but liquid cannot flow from channel I2i into either channel i3 or d6, and distributing channel il is connected to the supply passage 6e (Fig. 5) in each of bridges 2li, 24a, fib and 2da.

Distributing channel 12| may be an internal passage formed within the pump structure but for the purpose oi illustration it has been shown in Fig. 9 as an external channel and as being connected to the supply passages in bridges 24, 24e, Zlib and 24C through channels 25, i252, i25b and |25c respectively. As shown in Figs. l and 5 channel |25 has its inner portion arranged radially within cheek plate l0 with its inner end in communication with the passage S9 in bridge 2li and its outer portion extending axially through cover plate il and end head 3 so that it passes around gear pump ill-i8. As shown in Fie. 1, channel i251 extends axially through end head 3, cover plate il and cheek plate ill into communication with the passage 59 in bridge 24h. Channels |25au and 425C are the same as channel 125b and are indicated schematically in Fig. 9 but do not appear in the other figures.

It has previously been explained that in a vane type hydrodynamic machine the inner ends of the vane slots register successively with a plurality of vane slot ports which are formed in the inner face of one of its cheek plates and that liquid may flow to and from the vane slot ports through channels which communicate therewith and through which pressure maybe transmitted for urging the vanes outward against the vane track.

Since such an arrangement of vane slot ports is well known, it has not been completely illustrated in detail but has been shown schematically in Fig. 9 which is diagrammatic with the central portion thereof representing a view looking from the left end of spacer ring 5 toward 'the right in respect to Fig. l with rotor 6 removed to expose the central portion of the rear face voi' cheek plate it, rotor 6 being indicated by a dot and dash circle.

As shown in Fig. 9, cheek plate it has formed in its rear or inner face four arcuate vane slot ports i3l, 132, 1133 and i343, which are spaced radially inward from ports di, 4P, 4in and lc respectively, and four short vane slot ports 35. 36, |31 and i3d which are spaced radially inward from bridges 24, 2da, 24D and 2d@ respectively. Vane slot ports 31 and E32 also appear,

in Fig. 'I and vane slot ports 135 and i3? also appear in Fig. i.

During rotation of the rotor, each vane moves radially outward and draws liquid into its slot from a vane slot port as its outer end travels along the vane track from a sealing bridge to a working bridge, the outer end portion of the vane transfers liquid from an intake port to a discharge port as it passes across the working bridge, and the vane moves radially inward and ejects liquid from its slot into a vane slot port as its outer end travels along the vane track from the working bridge to the adjacent sealing bridge.

Vanes passing across the working bridge thus pump a principal volume of liquid and the vanes in moving radially pump a secondary volume of liquid which is proportional to the principal volume and equal to a substantial portion thereof. For example, the pump shown is capable of pumping 32,00) cu. in. per minute due to the passage of its vanes across the working bridges and approximately 3000 cu. in. per minute due to the radial movement of its vanes, thus making a total discharge of yapproximately 35,000 cu. in.

- per minute.

When the machine is used as a pump, the rotor is rotated at high speed and it is ordinarily only necessary to hydrostatically balance the vanes as the centrifugal force is ordinarily sufficient to hold the vanes in contact with the vane track but, when the rotor is rotated at slow speed and when the machine is functioning as a motor and is started under a load, the vanes must be positively urged against the vane track.

In order to hold the outer ends of the vanes in contact with the track surfaces on the bridges, the vane slot ports which are spaced radially inward from the bridges are supplied with liquid first at a low pressure and then at pump pres-- sure, a pressure higher than pump pressure being unnecessary as the outer end portions of a vane has pump pressure on one side thereof and a low or negative pressure on the other side thereof during almost its entire journey across the track surface on a bridge so that pump pressure acts upon only Va portion of the outer end area of the vane.

The vane slot ports spaced inward from the bridges may be connected to each other by a channel formed in the pump structure and that channel connected to suitable sources of pressure but for the purpose of illustration vane slot ports i315, |36. le? and 13s have been shown in Fig. 9 as being connected, respectively, to channels 125, iza, i25b and |25c by channels ldd, liii, M2 and i513 respectively. Channels i4!) and M2 also appear in Fig. l.

In order to utilize the liquid pumped by the radial movement of the vanes andto provide pressure for urging the varies outward against thevane track, the vane slot ports spaced in-i ward from the intake ports are connected to each other, to the gear pump and to one side of the external circuit and the vane slot ports spaced inward from the discharge ports are connected to each other, to the gear pump and to the other side of the external circuit.

As shown in Fig. 9, vane slot ports |3| and |33 are'connected to each other by a channel |44 which is formed within the interior of cheek plate It, they are also connected through a channel |45 and a check Valve |45 to gear pump supply channel |65 and are also connected through a channel |41, a check valve |48 and a resistance valve |43 to channel 43. Vane slot ports |32 and |34 are connected to each other by a channel |59 which is formed within the interior of cheek plate I6, they are also connected through a channel i5! and a check valve |52 to gear pump supply channel |68 and are also connected through a channel |53, a check valve |54 and a resistance valve |55 to channel 46.

Check valves ist and |54 permit liquid to ow from the external circuit into the vane slot ports connected thereto but they prevent fiow from those ports into the external circuit except through resistance valves |69 and |55. Check valves |46 and |52 prevent liquid from flowing from the vane slot ports connected thereto into channel |08 but they permit liquid to flow from channel |08 to the inner ends of the outward moving vanes whenever, as is usually the case, the liquid delivered to the inner ends of those vanes from the external circuit is insufficient to keep their slots filled with liquid.

Resistance valve ltd has two ports It@ and ||3| formed in its casing |52 and connected, respectively, to channels 43 and |41. Communication between ports |66 and |6| is controlled by a valve |63 having a piston |54 arranged upon its inner end and tted in a bore |65 formed in casing |62. Port |66 communicates with the inner part of bore |65 through a duct |66 which extends axially rthrough valve |53 and piston |64 so that whatever pressure is prevailing in port |66 will act upon the inner or large face of piston |64 and urge valve |63 toward its seat, valve |53 being in'- itially urged against its seat by a light spring 6'! arranged in the inner part of bore |65.

Port |6| communicates with the outer end of bore |65 through a slot |58 which is formed in the periphery of valve |63 so that whatever pressure is prevailing in port HI will act upon the outer or small face of piston |64 and tend to move valve its away from its seat to open communication between ports |63 and idi. The parts are so proportioned and the tension of spring |57 is such that the drop in pressure across resistance valve |59 is somewhat greater than the pressure created by gear pump |'|-|8. For example, resistance valve |49 may be adapted to open in response to the pressure in port l5! becoming 100 p. s. i. greater than the pressure in port |50. Since resistance valve |55 is identical to resistance valve M9, its parts have been indicated by the same reference numerals that are applied to corresponding parts of resistance valve |49 and a description thereof is deemed unnecessary.

` The arrangement is such that, when the parts are in the positions shown and rotor 6 is rotated in the direction of the arrow so that the pump is discharging through ports liliL and 4|c into channel 46, liquid returned from the circuit will ,flow through channel 43 to ports I and 4 ib, liquid may flow into vane slot ports |3| and |33 from channel 43 through check valve |46 and channels |41 and |44 and from channel |98 through check Valve It and channels |45 and |44 to keep theslots of the outward moving vanes lled with liquid at gear pump pressure so that the outward moving vanes have their inner ends subjected to gear pump pressure which holds the outer ends thereof in engagement with the vane track. As the vanes pass from a working bridge to a sealing bridge, they will be forced inward by the vane track and the outer ends of the vanes will be subjected to the pressure created by the pump which pressure if unopposed would move the vanes inward out of engagement with the vane track. However, the inward moving vanes will eject liquid from their slots into vane slot ports |32 and i3@ from which this liquid can escape, due to check Valves |52 and |54, only through resistance valve |55 which prevents the discharge of liquid therethrough until the inward moving vanes have created a pressure which is enough higher than pump pressure to enable the liquid acting upon the small area of piston |64 to exert a force which exceeds the total force exerted upon the large area of piston |64 by the pump pressure and by spring |57. Then resistance valve |55 will open and permit the liquid pumped due to radial movement of the vanes to ow'into channel 45 to augment the liquid pumped due to rotary movement of the vanes, and the pressure required to open resistance valve |55 will act upon the inner ends of the inward moving vanes and positively hold the outer ends of those vanes in engagement with the vane track.

When bridges 24 and 24h are moved to their innermost positions and bridges 24a and 24 are moved outward, the pump will function in the above described manner except that the flow to and from the main and vane slot ports will be reversed. That is, thel pump will discharge through main ports 4| and 4| b into channel 43, main ports 4 |F- and 4| C will be supplied with liquid through channel 4E, vane slot ports |32 and |34 will be supplied with liquid through one or both of check valves |52 and |55, the vanes passing across ports di and 4U will be forced inward by the vane track and will eject liquid from their slots into vane slot ports |3| and |33, and escape of liquid from vane slot ports I3! and |33 will be prevented by check valves |46 and |48 except through resistance valve its which will cause the inward moving vanes to create sufficient pressure to hold the outer ends of those vanes in engagement with the vane track.

In prior hydrodynamic machines of the sliding vane type, the vane slot ports formed in the inner face of a cheek plate were customarily connected to channels which were formed in the opposite face of the cheek plate and closed on their open sides by the flat surface that constituted the bearing for the cheek plate. The pressure in these channels caused liquid to seep between the outer face of the cheek plate and the supporting flat surface and form a nlm therebetween, the pressure in the high pressure channels would extend into the llxn adjacent those channels, and the pressure in the high pressure channels and in the adjacent nlm would cause the cheek plate to yield inward toward the rotor. Since there is only a running clearance between the inner face of a cheek plate and the end of the rotor, a very slight yielding of the cheek plate would cause it to engage the end ofthe rotor and impose a drag or brake load thereon and thereby not only decrease the efciency of the machine but also cause 5. In a pump having alternate intake and discharge ports, a substantially elliptical vane track including alternate working and sealing bridges each of which is arranged between a discharge port and an intake port, a vane slot port arranged radially inward from each of said ports, a rotor arranged within said track and provided with substantially radial vane slots each of which is adapted to register with said vane slot ports successively as said rotor rotates, vanes fitted in said slots with the outer ends thereof in engagement with said track and means for rotating said rotor to cause the vanes as they pass across a working bridge to pump liquid into the adjacent discharge port and to cause the vanes as they pass across a discharge port to be forced inward by said track and to expel liquid from their slots intol the vane slot port which is radially inward from that discharge port, the combination of a source of low pressure liquid, means for supplying liquidfrom said source to said vane slot ports to urge said vanes against said track, means for connecting each of said intake and discharge ports to the vane slot port that is radially inward therefrom, means included in said last mentioned means for resisting the discharge of liquid from each .vane slot port which is radially inward from a, discharge port to thereby cause the pressure in that vane slot port to exceed the pressure in said discharge port, and means for preventing high pressure in a vane slot port from extending to said source.

6. In a pump having alternate intake and discharge ports, a substantially elliptical vane track including alternate working and sealing bridges each of which is arranged between a discharge port and an intake port, a vane slot port arranged radially inward from each of said ports, a rotor arranged within said track and provided with substantially radial vane slots each of which is adapted to register with said vane slot ports successively as said rotor rotates, vanes iitted in said slots with the outer ends thereof in engagement with said track and means for rotating said rotor to cause the outer end portions of said vanes as they pass across a working bridge to pump a main volume of liquid through the adjacent discharge port and to cause the vanes as they pass across a discharge port to be forced inward by said track and to expel liquid from their slots into the vane slot port which is radially inward from that discharge port, the combina tion of a source of low pressure liquid, means for supplying liquid from said source to said vane slot ports to urge said vanes against said vane track, means for connecting a discharge port to the vane slot port that is radially inward therefrom so that the liquid expelled by inward moving vanes into said vane slot port may be added to saidmain volume, a resistance valve included in said last mentioned means to resist discharge of liquid from said vane slot port to thereby cause 18 the pressure in said vane slot port to exceed the pressure in said discharge port, and means for preventing high pressure in said vane slot port from extending to said source.

7. In a hydrodynamic machine having a rotor provided with substantially radial vane slots and vanes slidably fitted in said slots, a spacer ring arranged around said rotor and providing a space between its inner periphery and said rotor, alternate high pressure and lowvpressure main ports communicating with said space, and a vane track arranged around said rotor inside said spacer ring to cause said vanes to move radially during rotation of said rotor and including a plurality oi bridges each of which is arranged between a high pressure main port and a low pressure main port, the combination of cheek plates arranged upon opposite ends of said ring to enclose said rotor, at least one of said cheek plates having formed in its inner face a small vane slot port radially inward from each of said bridges and a larger vane slot port radially inward from each of said main ports and also having apassage leading radially outward through its interior from, each of said vane slot ports, said vane slot ports being so located that the inner ends of said vane slots register therewith successively during rotation of said rotor so that slots containing outward moving vanes may be supplied with liquid from vane slot ports and inward moving vanes may eject liquid from their slots into vane slot ports, a source of low pressure liquid, means for supplying liquid from said source through said passages to said vane slot ports to urge said vanes against said vane track, means responsive to the pressure in a high pressure port exceeding the pressure at said source for supplying liquid at a pressure higher than the pressure at said source to said small vane slot ports through the passages leading therefrom, means for resisting the discharge from said larger vane slot ports of liquid ejected thereinto by said inward moving vanes to thereby cause said inward moving vanes to create in their slots a pressure higher than the pressure at said source, and means for preventing said higher pressure from extending to said source.

WALTER FERRIS.

References Cited in the iile of this patent UNITED STATES PATENTS Number Name Date Re. 22,159 Centervall Aug. 18, 1942 2,255,785 Kendrick Sept. 16, 194i 2,255,787 Kendrick Sept. 16, 1941 2,256,459 Kendrick Sept. 16, 1941 2,335,567 Kay Nov. 30, 1943 FOREIGN PATENTS Number Country Date 531,232 Great Britain Dec. 31, 1940 

